If you live north of the 49th, you’ve probably already felt the chill of a long winter. Next time you’re shivering, think about whether you should invest in some insulated curtains.

The rundown

Thermal, or insulated, curtains are heavy drapes that help keep heat in (in winter) or out (in summer). They’re made from heavy-duty material, and often have a spongy insulated core. Although they may sound dowdy, insulated curtains come in a huge range of color, length, and style. You can also insulate your own curtains by adding a liner or starting from scratch.

Increase your efficiency

We all love big windows, but yours can contribute 10 to 25% of your winter heating bill simply by letting the heat out. There are a number of ways to mitigate this problem, including installing storm windows or “low-e” film. Curtains and shades increase the energy savings, but make sure your windows’ and storms’ are already well-insulated, or your curtains won’t be that effective.

Keep curtains open during daylight hours and maximize your solar energy absorption. But as soon as the sun goes down, close up shop.

You may want to…

Choose floor-to-ceiling drapes. They’ll help keep the cold from moving from the window into the room.

Use magnetic strips, sealing the curtain to the wall.

Check whether the curtains have flame retardant chemicals in them. Although some people choose this as a safety precaution, others feel that the chemical’s fire safety benefits don’t outweigh potential health effects.